Add cash (bills and coins), ID, important telephone numbers, account numbers, insurance info, safe deposit key, phone card, etc. IMHO, these are the most forgotten type of items in most BOBs.

BTW, if you have a lady friend/spouse - make sure you get her input on her requirements as well if this is going to be an all-inclusive kit. Even if she has her own, redundancy with her kit is not a bad idea because you might be able to grab only the one kit.

Add a change of clothes/footwear/eyewear in this bag. If you are bugging out because of fire, tornado or something that has damaged your house, you will appreciate this.